Plasma noradrenaline as an indicator of functional state in hearts with mitral stenosis: The influence of acutely reduced left atrial pressure by balloon mitral commissurotomy

Summary To investigate the mechanism in which plasma noradrenaline concentration (pNA) is elevated in heart failure, the effect of balloon mitral valvulo-plasty was used as a model of acute manipulation of the left atrial pressure reduction in ten patients with mitral stenosis. Gorlin mitral valve area and pNA were correlated with New York Heart Association functional class and found to have a significant exponential inverse relationship with each other ([pNA, pg/ml] = 198.9 × [mitral valve area, cm²]^–0.696;P = 0.003). Elevated pNA could be partially explained by a reduced cardiac index (CI) ([pNA, pg/ml] = 403.4 × [CI, l/min/m²]^–0.889;P = 0.027;r = 0.495), especially in severely failed hearts, but not by pulmonary capillary wedge pressure (PCWP). However, the percent changes (%) of variables early after balloon valvulo-plasty exhibited aparadoxical contrast; % pNA showing a clear negative exponential correlation with % PCWP ([% pNA] = 436.0 × [% PCWP + 80]^–0.679 – 80;P = 0.021), but not with % CI. These results suggest that pNA should be considered an indicator of cardiac functional class in mitral stenosis. PNA is modulated by both cardiac index and pulmonary capillary pressure, but in different ways.     

Further identification of protein kinase C isozymes in mouse epidermis

In the current study, the protein kinase C (PKC) isozymes present in mouse epidermis have been identified using immunological and chromatographic methods. Six PKC isozymes, PKC, PKC, PKC, PKC, PKC, and PKC, were identified in unfractionated epidermal preparations by protein immunoblotting. The subcellular distribution and presence of these isozymes was further verified by hydroxyapatite (HA) chromatography with the exception of PKE, which could not be detected following HA chromatography. The five PKC isozymes recovered following HA chromatography were detected in both epidermal cytosol and particulate fractions, although PKC was found in a much higher proportion relative to the other PKC isozymes in the particulate fraction using histone H1 as the substrate. The biochemical properties of the epidermal PKC isozymes partially purified by HA chromatography agreed with those reported for other tissues and further supported their immunological identification in epidermal preparations. The activities of HA chromatography peaks corresponding to PKC, PKC, and PKC were found to be dependent on both Ca²⁺ and phosphatidylserine (PtdSer), whereas, the activities of HA peaks corresponding to PKC and PKC were Ca²⁺-independent but PtdSer-dependent. The HA peak corresponding to PKC also displayed a characteristic biphasic modulation by arachidonic acid (activation at low, inactivation at high concentrations) and inactivation by preincubation with PtdSer. PKC activity was also characteristic, in that it was dependent on PtdSer and was not increased by the phorbol ester, 12-O-tetradecanoylphorbol 13-acetate. Some differences in substrate specificity were also observed between the epidermal PKC isozymes. The presence of multiple isozymes of PKC in mouse epidermis suggests that the different isozymes may play distinct roles in signal transduction and tumor promotion in this tissue.Abbreviations PKC protein kinase C - HA hydroxyapatite - PtdSer phosphatidylserine - TPA 12-O-tetradecanoylphorbol 13-acetate This work was supported by USPHS grants CA 38871 (J.D.), CA 57596 (J.D.) and core grant CA 16672     

Selective A2A adenosine agonist ATL-146e attenuates acute lethal liver injury in mice

Background d-Galactosamine (GalN)/lipopolysaccharide (LPS)-induced liver injury is an experimental model of fulminant hepatic failure in which tumor necrosis factor- (TNF-) plays a pivotal role. We examined the effects of a highly selective adenosine A_2A receptor agonist (ATL-146e) on GalN/LPS-induced fulminant hepatic failure.Methods Mice were given an intraperitoneal dose of GalN (800mg/g body weight)/LPS (100ng/g body weight) with and without ATL-146e (0.01µg/kg) treatment. Liver injury was assessed biochemically and histologically. Also, TNF- levels in the serum were determined.Results The serum liver enzyme (ALT) level in vehicle-treated mice was 20960 ± 2800IU/ml and was reduced by 63% to 7800 ± 1670IU/ml by treatment with 0.01µg/kg per minute ATL146e, P < 0.05. Treatment with ATL-146e significantly reduced serum TNF- and greatly reduced inflammation assessed by histopathologic examination compared with control mice treated with GalN/LPS. ATL-146e also reduced lethality at 12h from 65% to 13%.Conclusion The present findings suggest that the highly selective adenosine A_2A receptor agonist (ATL-146e) prevents endotoxin-induced lethal liver injury by suppression of TNF- secretion.     

Biochemical and clinical studies of a new case of α-aminoadipic aciduria

A mentally retarded, 10-year-old female with obesity, hypotonia, clumsiness and mild ocular abnormalities excreted in her urine large amounts of -aminoadipic acid. Amino acid analyser studies and gas-liquid chromatography-mass spectrometry (GC-MS) confirmed the presence of -aminoadipic acid in both urine and plasma but, in contrast to most other patients with this disorder, failed to demonstrate significant levels of -ketoadipic acid in urine. Other known causes of -aminoadipic aciduria were eliminated by showing that levels of lysine, saccharopine and pipecolic acid in plasma and urine were normal and that the activity of glutaryl-CoA dehydrogenase was also normal.Loading with L-lysine and L-tryptophan both increased the concentration of -aminoadipic acid in blood and urine compatible with a primary deficiency of -ketoadipate dehydrogenase, in spite of the absence of -ketoadipic aciduria. Dietary restriction of lysine and administration of vitamins B₁ and B₆ were unsuccessful in correcting the biochemical abnormality.     

Effects of human α-interferon on granulocyte-macrophage progenitor cells (CFU-GM) in vitro

Summary Two preparations of human interferon (IFN)- were assessed for their influence on granulocyte-macrophage progenitor cells (CFU-GM) in vitro. Both highly purified human IFN- Ly and recombinant IFN- 2a suppressed CFU-GM colony formation in a dose-dependent manner using low-density bone-marrow target cells. Suppression of CFU-GM colony formation was accompanied by an increase in clusters. However, depletion of monocytes, T lymphocytes and B lymphocytes from low-density bone-marrow cells resulted in insensitivity of progenitor cells to IFN-. These results demonstrate that the effects of human IFN- on myeloid progenitor cells (CFU-GM) are mediated by accessory cells within the bone marrow.     

Hepatic expression of interferon-α in chronic hepatitis B virus infection

Hepatic expression of interferon- (IFN-) was examined by immunohistochemistry in 90 Chinese patients (M/F 67:23, age: 14–69) with a spectrum of hepatitis B virus (HBV)-related chronic liver diseases. Immunoreactive IFN- was detected in sinusoidal cells in 79 patients (88%) and in mononuclear cells in 59 patients (65.6%). Patients with active liver diseases (chronic active hepatitis, active cirrhosis,N=55) had a higher level of IFN- expression compared to patients with inactive histology (N=35; sinusoidal cells,P<0.01; mononuclear cells,P<0.01). Cytoplasmic HBsAg, nuclear HBcAg, and cytoplasmic HBcAg were detected in 79 (88%), 42 (47%), and 23 (27%) patients respectively. Expression of IFN- in mononuclear cells correlated with the expression of cytoplasmic HBcAg (P<0.05) but not with nuclear HBcAg or cytoplasmic HBsAg. When the patients were divided into four different phases according to the natural history of chronic HBV infection, patients in the active liver disease phase had higher IFN- expression compared to the immunotolerant and late phase patients (P<0.01). Using double immunohistochemical staining, both IFN- and cytoplasmic HBcAg were frequently detected near inflammatory infiltrates but no correlation existed between the hepatic expression of HBsAg and IFN-. These data indicate that IFN- is expressed in the liver in HBV-related active liver diseases and that the reported suboptimal production of IFN- by PBMC in HBV-related chronic active liver diseases may be due to a redistribution of the IFN--producing mononuclear cells into the liver, the site of inflammation.     

Interleukin-1β Inhibits Growth Factor-Stimulated Restoration of Wounded Rat Gastric Epithelial Cell Monolayers

We examined the effect of interleukin-1(IL-1) on spontaneous and enhanced restoration(cell migration and proliferation) using an in vitrowound model comprising a confluent monolayer of ratgastric epithelial RGM1 cells. Repair of an artificialwound in a cell monolayer was found to be time- andconcentration-dependent when the cells were incubatedwith epidermal growth factor (EGF) or transforming growth factor (TGF)- alone for up to 24hr. The growth factors also stimulated DNA synthesissignificantly for 24 hr in a concentration-relatedmanner. IL-1 had no effect on wound restoration in the absence of the growth factors. However, itmarkedly inhibited the restoration enhanced by EGF andTGF-, the inhibition being about 60% and 70%,respectively. In addition, IL-1 significantly reduced the DNA synthesis stimulated by thegrowth factors. The EGF- and TGF--enhancedrestoration was reduced by about 30% by mitomycin C,which potently inhibited the stimulated DNA synthesis.Mitomycin C had no effect on the spontaneous restoration.Even when treated with mitomycin C, the inhibitoryeffect of IL-1 on the enhanced wound repair wasstill observed; however, the extent of the inhibition was decreased. These results indicate thatIL-1 inhibits the migration as well as theproliferation of gastric epithelial cells enhanced byEGF and TGF-, resulting in a failure of woundhealing.     

B cell adrenoceptors and sulphonylurea-induced insulin release in mouse islets

Summary Interactions of tolbutamide and glibenclamide with B cell adrenoceptors have been reported. This study evaluated the possible role of such interactions in the stimulation of insulin release. Mouse islets were incubated in the presence of 10 mmol/l glucose alone or with tolbutamide (10 mol/l) or glibenclamide (0.02 mol/l). At 0.01–10 mol/l, blockers of ₂-adrenoceptors (yohimbine, idazoxan) or ₁-adrenoceptors (prazosin) had practically no effect on glucose-induced insulin release and did not affect its potentiation by sulphonylureas, except for a slight increase by 10 mol/l prazosin and idazoxan. Nonspecific -blockers (phentolamine, dihydroergotamine) increased control release at 10 mol/l, but only the latter amplified the response to tolbutamide. Blockers of -adrenoceptors were tested at 0.1–100 mol/l: propranolol (₁, ₂), metoprolol (₁) and compound ICI 118-551 (₂). They increased glucose-induced insulin release at 100 mol/l but variably altered the effect of sulphonylureas. Blockers of adrenoceptors have, thus, no effect on insulin release in vitro at therapeutic concentrations. At high concentrations, they non-specifically affect the action of sulphonylureas. We conclude that an interaction with B cell adrenoceptors is not involved in the insulinotropic action of sulphonylureas.     

Performance of a Fourier-based program for three-dimensional reconstruction of the mitral annulus on application to sparse, noisy data

Objectives: We investigated the accuracy of mitral annular reconstruction from noisy, sparse data typical of three-dimensional (3D) transthoracic echocardiograms. Background: Our Fourier-based method for reconstructing the annulus from dense, accurate 3D transesophageal echo (TEE) data has been validated in vitro with four harmonics in the x, y, and z coordinates (4,4,4). Methods: Thirteen mitral annuli were reconstructed from complete 3D TEE data using four harmonics (4,4,4) and used to measure area, eccentricity, height, perimeter, and interpeak and intervalley distances; these were the true values. To simulate transthoracic echo data, the TEE data sets were reduced evenly and unevenly (randomly). The complete and reduced data sets were used to reconstruct the annuli using three sets of fitting parameters: (4,4,4), (1,1,3), and (1,1,4). The resulting size and shape measurements were compared with true values. Results: Regardless of the fitting parameters used, area, 2D perimeter, and 3D perimeter measurements were more accurate using reconstructions from evenly-reduced than randomly-reduced data sets (p < 0.006), and depended significantly on both data density (p < 0.015 for all) and data distribution (p < 0.02 for all). Perimeter, height, and eccentricity of the reconstructed annuli were more accurately measured using four harmonics (4,4,4). Conclusions: Mitral annuli can be reconstructed from sparse, noisy data using the (4,4,4) fit if at least 25 points are obtained from evenly distributed imaging planes. These results suggest that detailed analysis of mitral annular size and shape can be made accurately from 3D transthoracic echocardiograms.     

Role of Central Interleukin-1β in Gastrointestinal Motor Disturbances Induced by Lipopolysaccharide in Sheep

Cytokines are involved in the symptoms of theacute phase response induced by infectious diseases inhumans as well as in animals, and interleukin-1(IL-1 ) has a pivotal role in these changes. The role of central IL-1 in the gastrointestinalhypomotility and fever evoked by intravenousadministration of lipopolysaccharide (LPS) and themechanisms involved, were investigated in sheep as anexperimental model. LPS (0.1 g/kg, intravenously)induced gastrointestinal hypomotility and fever thatwere significantly reduced by priorintracerebroventricular administration of IL-1receptor antagonist protein (IL-1ra, 2 g/kg). The effects of LPS were mimickedby intracerebroventricular IL-1 (50 ng/kg),whereas IL-1 injected intravenously at the samedose only caused a slight and transient fever withoutmodifying the gastrointestinal motility. Priorintracerebroventricular administration of thecyclooxygenase inhibitor indomethacin (100 g/kg) butnot the corticotropin-releasing factor (CRF) receptorantagonist -helical CRF_9-41 (5 g/kg) blocked alleffects evoked by both LPS and IL-1. These resultssuggest that in sheep, LPS induces digestive motordisturbances through a central release of IL-1 andprostaglandins.     

Isolierung von freien Nucleotiden aus verschiedenen Geweben

Zusammenfassung In Erweiterung früherer Mitteilungen wird über den Gehalt des Flexner-Jobling-Carcinoms der Ratte an freien Nucleosidmono- und-polyphosphorsäureestern berichtet.Die vorliegenden Untersuchungen wurden zum Teil dankenswerter-weise durch denAnna-Fuller-Fund und dieDeutsche Forschungsgemeinschaft unterstützt.In der Arbeit werden folgenden Abkürzungen verwendet Ad Adenosin - AMP Adenosin-5-monophosphat - ADP Adenosin-5-diphosphat - ATP Adenosin-5-triphosphat - GMP Guanosin-5-monophosphat - GDP Guanosin-5-diphosphat - GTP Guanosin-5-triphosphat - CMP Cytidin-5-monophosphat - CDP Cytidin-5-diphosphat - CTP Cytidin-5-triphosphat - UMP Uridin-5-monophosphat - UDP Uridin-5-diphosphat - UTP Uridin-5-triphosphat - UDPA Uridin-5-diphosphat-N-acetylglucosamin - UDPG Uridin-5-diphosphat-glucose - UDPGa Uridin-5-diphosphat-galaktose - UDPGl Uridin-5-diphosphat-glucuronsäure - IMP Inosin-5-monophosphat - DPN Diphosphopyridinnucleotid - HS Harnsäure - RNS Ribonucleinsäure - DNS Desoxyribonucleinsäure - TPN Triphosphopyridinnucleotid Mit 19 TextabbildungenDer überwiegende Teil der dieser Arbeit zugrunde liegenden Versuche wurde 1952/53 im McArdle Memorial Laboratory, University of Wisconsin durchgeführt.     

Schindler disease: An inherited neuroaxonal dystrophy due to α-N-acetylgalactosaminidase deficiency

Summary The clinical, pathological and biochemical features of a neuroaxonal dystrophy resulting from the deficient activity of lysosomal -N-acetylgalactosaminidase are described. This neurodegenerative disorder was recognized in two brothers who had the typical clinical manifestations and neuropathological lesions observed in patients with Seitelberger disease, the infantile form of neuroaxonal dystrophy. Axonal spheroids were observed histologically in the grey matter, and ultrastructural examination revealed the characteristic formations in dystrophic axons in the myenteric plexus and neocortex. Using a newly synthesized fluorogenic substrate, 4-methylumbelliferyl--N-acetylgalactosaminide, the markedly deficient activity of-N-acetylgalactosaminidase was demonstrated in the affected brothers while their consanguineous parents had intermediate activities, consistent with the autosomal recessive transmission of this disease. No detectable-N-acetylgalactosaminidase was seen in immunoblots using monospecific rabbit antihuman-N-acetylgalactosaminidase antibodies. Abnormally increased amounts of urinary glycopeptides were observed by high resolution thin layer chromatography. Analytical studies identified four of the accumulating urinary compounds, the blood group A trisaccharide GalNAc1 3(Fuc1 2)Gal and threeO-linked glycopeptides, GalNAc1 O-serine and -threonine, NeuNAc2 3Gal1 3(NeuNAc2 6)GalNAc1 O-serine and -threonine, and NeuNAc2 3Gal1 4GlcNAc1 6(NeuNAc2 3Gal1 3)GalNAc1 O-serine and -threonine. Of eight unrelated patients diagnosed as having infantile neuraxonal dystrophy by pathological studies, none had deficient-N-acetylgalactosaminidase activity, emphasizing the biochemical heterogeneity underlying this diagnostic entity. These findings document the first delineation of a metabolic defect in an inherited neuroaxonal dystrophy and suggest that the axonal pathology in this disorder, and perhaps in the other neuroaxonal dystrophies, results from abnormal glycoprotein metabolism involvingO-linked glycopeptides.     

GlutathioneS-transferase expression in malignant mesothelioma and non-neoplastic mesothelium: an immunohistochemical study

Expression of the glutathioneS-transferase (GST) subclasses , and was investigated immunohistochemically in 20 normal or hyperplastic mesothelium and in 57 malignant mesothelioma cases. These results were correlated with survival and also with P-170 glycoprotein expression. Nearly all the non-neoplastic mesothelium cases were positive for GST and . About half of the non-neoplastic cases were positive for . Twenty-nine (51%) malignant mesotheliomas were positive for at least one of the GST species; 21 (37%) showed immunoreactivity for , 18 (31.5%) for and 21 (37%) for . A total of 54 mesothelioma cases displayed immunoreactivity for the P-170 glycoprotein. For GST and GST, a statistical significance between expression and increased survival was found (respectivelyP=0.012 and 0.024) while for GST no significance was found. The results of this study demonstrate that expression of GST correlates positively with increased survival in malignant mesothelioma. It is also concluded that, in mesothelioma, GST and P-170 glycoprotein may contribute to the resistance to cytotoxic drugs frequently observed in these tumours. No correlation between GST and P-170 expression was demonstrated.Abbreviation GST glutathioneS-transferase     

Comparative and combined effects of transforming growth factors α and β, interleukin-1 and interferon-γ on rheumatoid synovial cell proliferation,glycolysis and prostaglandin E production

Summary Enhanced cell proliferation, glycolysis and prostaglandin E production are all characteristic features of rheumatoid synovial tissue. The interrelationships of these three cellular parameters have been examined using rheumatoid synovial fibroblasts and their responses to specific cytokines in vitro. Transforming growth factor (TGF) caused a more than threefold increase in synovial cell proliferation whilst transforming growth factor (TGF), interleukin-1 (IL-1) and interferon- (IFN-) produced only marginal changes. The combined addition of IL-1 with TGF resulted in an enhanced proliferative response comparable with that produced by TGF. Glycolysis, estimated by glucose utilisation and measurements of the glycolytic regulatory metabolite fructose 2,6-bisphosphate was significantly stimulated by TGF, IL-1 and IFN-, but less so by TGF. Prostaglandin E production was significantly increased by IL-1 to an extent much greater than that produced by TGF or TGF, although the combined addition of IL-1 with either TGF or resulted in a synergistic increase in PGE production, a response partly diminished by the addition of IFN-. These findings suggest that the extent to which a cytokine stimulates glycolysis is not consistently related to its mitogenicity, and that cytokine combinations which stimulate high levels of PGE production (a growth inhibitor) will not necessarily be associated with a reduced rate of cellular proliferation in cultured, adherent, rheumatoid synovial fibroblasts.     

Studies on the oxidation of phytanic acid and pristanic acid in human fibroblasts by acylcarnitine analysis

The -oxidation of phytanic acid and the -oxidation of pristanitc acid were investigated in cultured fibroblasts from controls and patients affected with different peroxisomal disorders using deuterated substrates. Formation of [-2H6]4,8-dimethylnonanoylcarnitine ([-2H6]C11-carnitine) from [-2 H6]phytanic acid and [-2H6]pristanic acid was used as marker for these processes. Analysis was performed by tandem mass spectrometry.In normal cells, formation of [-2H6]C11-carnitine from both [-2H6]phytanic acid and [-2H 6]pristanic acid was observed. When peroxisome-deficient fibroblasts were incubated with these substrates, [-2H6]C11-carnitine was not detectable or, in two cases, very low, which results from deficiencies in both peroxisomal - and -oxidation. In cells with an isolated -oxidation defect at the level of the peroxisomal bifunctional protein, formation of [-2H6]C11-carnitine could also not be detected.Cells with an isolated defect in the -oxidation of phytanic acid, obtained from patients affected with Refsum disease (McKusick 266500) or rhizomelic chondrodysplasia punctata (McKusick 215100), did not form [-2H6]C11 -carnitine from [-2H6]phytanic acid. The observed formation of [-2H6]C11-carnitine from [-2H6]pristanic acid in these cells is in accordance with a normal peroxisomal -oxidation in these disorders.This study shows that separate incubation of fibroblasts with [-2H 6]phytanic acid and [-2H6]pristanic acid, followed by acylcarnitine analysis in the medium by tandem mass spectrometry, can be used for screening cell lines for deficiencies in the peroxisomal - and -oxidation pathways.     

Plasma acidic glycohydrolases in insulin-dependent diabetes mellitus

Summary We assayed plasma activities of -galactosidase, -hexosaminidase, -mannosidase, -fucosidase and -galactosidase involved in degradation of the glycoprotein molecule in 110 insulin-dependent diabetics aged 3-1/2 to 19 years and compared them to a group of normal youngsters. We correlated the plasma enzyme activities with the duration, control and sequelae of insulin-dependent diabetes. Insulin-dependent diabetics had a significantly higher plasma activity of -hexosaminidase and -mannosidase (p<0.01) and a significantly lower plasma activity of -fucosidase and -galactosidase (p<0.01). Of the 5 enzymes studied, only plasma -hexosaminidase correlated with fasting and postprandial blood sugar (p<0.01), cholesterol and triglycerides (p<0.05). Additionally, poor control of diabetes was also associated with a significantly higher plasma -hexosaminidase activity (p<0.01). Proteinuria or an abnormal Addis count suggestive of renal involvement was associated with various changes in plasma acidic hydrolases. These changes may be related to insulin deficiency rather than hyperglycemia and may be genetically determined.Deceased on August 2, 1981.     

Interferonγ and tumour necrosis factorα induce a synergistic antiproliferative response in human Ewing's sarcoma cells in vitro

Three human cell lines derived from Ewing's sarcoma (RM-82, VH-64, and WE-68) were investigated to establish the influence of recombinant human interferon (rhIFN) and tumour necrosis factor (rhTNF) on cell proliferation and survival and to characterize IFN and TNF receptor expression. Incorporation of [³H]thymidine into cells was inhibited by rhIFN after 24 h of incubation. Half-maximal inhibition was observed with 10–80 U/ml rhIFN. A maximal effect (50%–70% inhibition of cell proliferation) was achieved by treatment of cells with 250 U/ml rhIFN. The influence of rhTNF on proliferation was found to differ among cell lines and varied with the concentration and the duration of exposure of cells to this cytokine. In WE-68 and VH-64 cells [³H]thymidine incorporation was not affected by rhTNF up to 2000 U/ml after 96 h of incubation, where-as in RM-82 cells the incorporation was inhibited by 35% after 48 h of incubation with 100 U/ml rhTNF. However, all cell lines showed a synergistic antiproliferative response to the combination of rhIFN and rhTNF after 24 h of incubation. The human recombinant cytokines interleukin(IL)-1, IL-1, IL-2, IL-3, IL-4, IL-6 and granulocyte/macrophagecolony-stimulating factor, tested alone and in combination with rhIFN and rhTNF, had no influence on cell proliferation. Binding studies in the cell lines with¹²⁵I-rhIFN revealed a dissociation constant (K _d ) of 160–306 pM and approximately 8000–13500 receptors/cell. Binding experiments with¹²⁵I-rhTNF indicated 430–1250 receptors/cell withK _d ranging from 13 pM to 162 pM. These data indicate that, among various cytokines, only IFN and TNF are capable of potently reducing Ewing's sarcoma cell growth in vitro. Our data suggest that IFN alone or in combination with TNF may be useful in the design of novel strategies in Ewing's sarcoma therapy.     

Inhibition of Parietal Cell Acid Secretion Is Mediated by the Classical Epidermal Growth Factor Receptor

Epidermal growth factor (EGF) and transforminggrowth factor- (TGF-) inhibit gastric acidsecretion both in vivo and in vitro. Previous studieshave indicated that EGF and TGF- bind to the same EGF/TGF- receptor. Nevertheless, weand others have previously demonstrated that inhibitionof acid secretion by these growth factors requiresconcentrations of the peptides that are 10-fold higher than those necessary for induction ofmitogenesis. Therefore, we have sought to investigatewhether gastric parietal cells may possess a secondEGF/TGF- receptor class. Two systems werestudied: First, [¹²⁵I]TGF- was cross-linkedto the receptor in isolated rabbit parietal cellmembranes, and labeled species were resolved onSDS-PAGE. Second, acid secretion was evaluated inpylorus-ligated waved-2 mutant mice, which carry a disabling pointmutation in their classical EGF/TGF- receptor. Inisolated parietal cells, [¹²⁵I]TGF-was cross-linked into a single species of 170 kDa.Cross-linking was inhibited in the presence of unlabeledTGF- with an IC of 80 nM. In the pylorus-ligatedmice, control littermate mice demonstrated adose-dependent inhibition of acid secretion by EGF withan IC of 20 g/kg. In contrast, EGF had noinhibitory effect on acid secretion in 50 waved-2 miceat concentrations up to 100 g/kg. No alterations inparietal cell or gastrin cell numbers were observed.These results in both isolated rabbit parietal cellsand waved-2 mice support the existence of only a singleclass of EGF/TGF- receptors in parietal cells.Differences in growth factor affinity are likely due to the modification of the receptor or oneof its coordinate regulators.     

Thalassemia intermedia: compound heterozygous β∘/β+-thalassemia and co-inherited heterozygous α+-thalassemia

Summary The relative excess of - over -globin chains in the erythroid precursors is the chief pathophysiological factor of homozygous -thalassemia. The clinical picture is usually characterized by a transfusion-dependent dyserythropoietic anemia (thalassemia major). However, some patients present with moderate anemia that does not require regular blood transfusions (thalassemia intermedia). The molecular heterogeneity of -thalassemia mutations and changes of - and -globin gene expression play an important role in modifying the clinical phenotype. We report here on a female Greek patient with homozygous -thalassemia but normal growth and development, excellent exercise tolerance, and no need of blood transfusions. She is thus mildly affected clinically, although there is marked pallor, jaundice, and hepatosplenomegaly. These signs correspond to her marked hypochromic, microcytic anemia with erythroid hyperplasia of the bone marrow. -Globin genotyping shows her to be compound heterozygous for the codon 39 C T -nonsense mutation and for the T C ⁺-mutation at position 6 of the splice consensus at the exon 1/intron 1 junction (CD39 C T/IVS 1–6 T C). -Globin gene mapping demonstrates the presence of a 3.7-kb ⁺-thalassemia deletion on one allele (–^3.7/). Taken together, this study identifies a complex interaction of genetic factors that do not significantly alter the clinical phenotype when present alone but ameliorate the course of homozygous -thalassemia when inherited in combination.Abbreviations Hb hemoglobin - Hct hematocrit - HPFH hereditary persistence of fetal hemoglobin - IVS intervening sequence - MCH mean corpuscular hemoglobin - MCV mean corpuscular volume - PCR polymerase chain reaction     

The antigenicity of human hemoglobins

Summary The correlation of the antigenicities among native hemoglobins and their subunit chains were investigated by the absorption of antisera and the combination of urea added immunoelectrophoresis with double diffusion. Alphachain showed identity with Hb-F but partial identity with -chain and Hb-A. Beta-chain showed identity with Hb-A but -chain and Hb-F showed partial identity with this chain. Gamma-chain showed identity only with Hb-F and its antigenicity was considered as being different from those of - or -chains.The lines of -, -and -chains were reconfirmed from the facts that the appearance of them depended always on the existence of anti-Hb-A or anti-Hb-F antibodies in the absorbed antisera and the minor component lines of

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Zusammenfassung Die Zusammenhänge der Antigenität zwischen nativen Hämoglobinen und deren Unterketten wurden mit der Absorption der Antiseren und der Kombination der Harnstoff-Immunelektrophorese und Doppeldiffusion untersucht. Die -Kette zeigte Identität mit Hb-F, aber nur partielle Identität mit der -Kette und Hb-A. Die -Kette war in ihrer Antigenität mit Hb-A identisch, die -Kette und Hb-F waren teilweise identisch mit der -Kette. Die -Kette zeigte die Identität mit Hb-F; es wird angenommen, daß ihre Antigenität verschieden von der -oder -Ketten ist.Für das Auftreten der Linien der -, - und -Ketten müssen Anti-Hb-A-oder Anti-Hb-F-Antikörper in den absorbierten Antiseren vorhanden sein, außerdem fusionieren die schwächeren Linien der Doppeldiffusion nicht mit irgendwelchen Linien der Unterketten. Auch gereinigte - oder -Ketten wurden zur Feststellung ihrer Linien benutzt.